Stack two monthly exports into one combined report with UNION

This month's export and last month's export sit in two separate query results, and the chart needs every row from both stacked into a single table.

Intermediate to advancedRead 6 minDoing: 30 to 45 minutes once you know both exports' columns, longer the first time a column turns out to be the wrong type7 steps

▶ Start

What you'll have at the end

One stacked report with a source label column, row count matching both original queries combined

Before you start

You need

Two monthly order exports, each already available as its own table or query result, with an order id, a customer id, an order date and an amount column.

Not covered

Deciding what to do when the same real order genuinely shows up in both months, such as a backdated correction, since that calls for removing the duplicate on purpose rather than stacking everything.

Leans on

7 steps

Where to go next

Standardize a status column so every capitalization spelling counts as one value

when the two exports also spell the same status differently, so grouped counts on the stacked report are already wrong before you get here

Checked 26 Aug 2026

Part of the SQL cookbook